Embedded Devices, Internet Access

The appearance of network technique with representative of Internet and the combination of the network technique and other relative techniques bring unprecedented development space and opportunity for remote measurement and control technology. Networking measurement and control technology and different kinds of new style instruments with network interface emerge as the times require. But it's difficult to embed the complicated network protocol into embedded system because of the limited resource, especially in 8-bit MCU.The paper discusses difficulty of technology to realize network communication in embedded devices. It represents and analyses TCP/IP suit for realizing network communication in embedded environment. Then, we design a networking data acquisition system that makes use of 51-MCU, NIC of Ethernet, A/D converter and relative peripheral interface circuit. It can be linked the Internet through the Ethernet. On software, we simplify TCP/IP suit, including UDP, ICMP, IP and ARP, made it run in 8-bit MCU, to implement the remote data acquisition. The system can receive the control request of remote clients, process the acquisition of analog signals, I/O control and remote transmission.